Improvement in draft-equalizers



J. F. DONOGHUE. DRAFT-EQUALIZER.

Patented May 9,1876.v

NER, WASHINGTON. Dl C.

N4 PETERS, PHOTO-LITHOGRAP coat-pipe for the smoke-box of a locomotive,

ordinary use, except that the pipe part 11, in-

.are arranged, as shown, to have their open UNITED STATES PATENT OFFICE,

JOHN F. DONOGHUE, OF SPRINQGFIELD, MASS-ACHUSETTS.A

IMPROVEMENT-IN DRAFT-EQuALl'zERs.

Specification forming part of Letters Patent N o. 177,107, dated May 9, 1876, application filed February 25, 1876.

To all whom it may concern:

Be itknown that I, J oHN F. DoNoGHUE, of Springfield, Massachusetts, have invented an Improvement relating to Locomotive-Engines, ot' which the following is a specification:

My invention consists in an improved pettiand has for its object the equalization of thev draft through the tlues andthe ability to mod'- ify the construction of the exhaustnozzle opening into,the,petticoatpipe, so as to permit slight compression of steam by it to always maintain a draft. Y

In the drawings, Figure I is a side eleva-- tion of my pipe, Fig. Il being a section on the line a: .fr of Fig. I.'

The lower section B corresponds to that in stead of extending to or nearly to the base of the smoke-stack, is 'shortened to form a neck to the part B; The part B has arranged above it the conical sections C D. These sections apices forml an uninterrupted smoke-passage from top of pipe b to the smoke-stack h, while having their sectional .areas least at the t-op of the pipe b and apex of section C, to form a pipe of a series of nozzles, represented respectively by the parts B, C, and D, the bases of which nozzles shall divide the space between the top and bottom of the smoke-box of the'locomotive, and shall equalize the draft, that has formerly' been to the bottom yof the pipe, through its length, and consequently'in a more or less directI line with all ot' the hues, the great advantage of which is that whereas, with the ordinary pettieoat-pipe, the lower ues are taxed to their utmost capacity, while the upper ones have little to do, with my pipe the draft is equal over all the lues, and' any increase of the blast through the exhaust-nozzle in equal proportions increases the capacity of the tire to makesteam. And it follows also that as all ot' the exhaustis utilized to increase the draft, less pressure is required to run at high speeds than has heretofore been by the arrow W may be directly carried into v the pipe, when deflected or crowded from the smoke-*space nearest'it, and that a direct draft may exist at all elevations I provide the sections C D with the hoods c d, which are' in effect as if the bases of thesections ot' which they form part were elliptical with the lowest and highest ends ot' the/ellipse inthe bases of the hood and section proper.

In Fig. I the small arrows show the course of the smoke and cinders. In Fig. II the sections are shown secured to each other by the riveted arms m, and the pipe is suspended in the usual way from the top ofthe smoke-box, while the nozzle ot' the blast or` exhaust pipe is introduced beneath-the section B.

Now, having described my invention, what I claim is pg A The petticoatpipe, consisting of the series of sections, constructed and arrangedas shown and described, to form a reduced space between'the nozzle of one and the wall of the succeeding section, and having the hoods c d, as and for the purpose set forth.

l JNO. F. DONOGHUE. Witnesses: A

B. F. HYDE, T. M. BROWN. 

